Air Purifier VS Humidifier VS Dehumidifier : Combo and Differences

If you have been shopping for air purifiers, you will probably notice usually there are 3 types of humidifier/ dehumidifier in the market: The air purifier humidifier, the stand-alone humidifier and the stand-alone dehumidifier. So what is the difference between the humidifier and dehumidifier? Should you get an air purifier with humidifier or just a stand-alone humidifier?

Short answer

Air purifier purify air. Humidifier increase humidity level. Dehumidifier decrease humidity level.

Long answer

  • How Air Purifier works
  • How Humidifier works
  • How Dehumidifier works
  • Air Purifier VS Humidifier
  • Air Purifier VS Dehumidifier
  • Humidifier VS Dehumidifier
  • Air Purifier VS Humidifier VS Dehumidifier
  • 1

    How Air Purifier Works

    How air purifier works is simple. Using various method and technology, air purifier circulates air through its filtration to remove airborne particles, smoke and allergens e.g. dust, mold, pollen,pet dander and odor. The complicated part is there are different or even multiple types of technology that could be involves in an air purifier. Let’s begin with the most popular, mechanical HEPA air purifier.

    Obligated to IEST/ UL industry standard, there are 2 types of HEPA filter: True HEPA filter that has a success filtration rate of 99.97% on particles as small as 0.3 microns VS inferior HEPA-type filter that a lesser 99% filtration rate on irritants as small as 2 microns. Deodorizer/ Odor eliminator on the other hand, focus more on smoke and odor particles that would have the same negative impact as other non-gas allergens if is not dealt properly. Higher grade activated carbon filter comes with infused that can even target strong chemicals like ammonia, chlorine, radon and VOCs.

    UV air purifier relies on ultraviolet radiation from UV lamps to eliminate biological irritants notably germ, bacteria and viruses. Proven and 100% safe as it is also the same technology that can be found in hospital or children sterilizer bottle. Like UV technology, PCO air purifier uses Photocatalytic Oxidation (PCO) technology that oxidize microorganisms and viruses as small as 0.001 microns. Very effective against germ and bacteria but the entire oxidation process is slow plus performance degrade overtime.

    Ionic air purifier or ionizer is a permanent purification technology that disperse charged ions onto the air. The electrostatically charged ions would merge with other airborne irritants to form a heavier particle that will due to the increased weight. The entire process is filterless and evergreen, but Ionic air purifier alone does not remove any particles. Electrostatic precipitator relies on Ionization technology that involves the merging of airborne negative ions and positive ions particles. Unlike Ionic air purifier, the heavier merged particles would fall into collector plate so you can focus on maintaining the Electrostatic air cleaner rather than vacuuming the entire room.

    Last but definitely the least loved, Ozone generator. Notoriously known for its part in damaging lungs, inhaling highly concentrated level of ozone would cause irreversible damage to our lungs. To make matter worst, studies shown ozone does not actually remove airborne particles or odors but rather mask them to confuse one’s senses.

    Do I need an Air Purifier?

    Are you staying near industrial area, highway or in a bad part of the neighbourhood. Are you a smoker or living around a smoker? Do you have pets that constantly shed or smell? Are you an asthmatic person that is hyper-sensitive to allergens like pollen? Do you constantly suffering from stuffy nose, excessive sneezing, watery eyes, frequent coughing and wheezing. If the answer to any one of the above is YES, then you do need an air purifier. Not just any air purifier, HEPA air purifier with multiple filtration. To save you the hassle going through all the current models, we recommend reading Best HEPA Home Air Purifier or Best Pet Dander Air Purifier.

      Benefits of Air Purifier

    • Remove allergen-triggering irritants like dust mites, pet dander or pollen. Also protect your respiratory system from related diseases.
    • Stop seasonal allergies, flu and even SARS by trapping microscopic allergens that cannot be seen through naked eyes.
    • Air purifier equipped with carbon filter can remove chemical gas, smoke and odor particles as well.
    • Technologies like UV-light that is highly effective in eliminating germs and bacteria from spreading.
    • Support autonomous operation where you leave the air purifier on 24×7 for at least couple of months.
    • Air purifier can reduce the number of dust in your house. Slower dust buildup means less frequent cleaning is needed.
    • At low speed, air purifier will run silently on the background without disrupting your daily routine.
    • Inexpensive for the compact/ small version while larger version is competitively priced as well.

      Disadvantages of Air Purifier

    • Only limited to airborne irritants. Air purifier cannot capture dust, pet hair or pollen that stuck on sofa or fall to the ground.
    • Has zero impact on room humidity level.
    • Models like Ozone generator will cause more damage to lungs rather than protecting it.

    How Humidifier Works

    Let’s get straight to how humidifier works. Humidifier release moisture to increase indoor humidity level. There are 4 types of humidifier: Evaporative, Steam, Ultrasonic and Impeller. The most common Evaporative humidifiers aka cool moisture humidifier or wick humidifiers, use a porous material to absorb water from the reservoir (water tank) and evaporate into the air via its internal fan. Another common choice is steam vaporizer/ warm mist humidifier that uses the classic boiling water method via its heating element. Depending on the models, the clean, boiled water would either be emitted directly (steaming hot) or let the temperature cool down in the machine before been release out. Ultrasonic humidifier uses a high frequency sound waves to create vapors that has the advantages of being completely silent (dost not rely on fan), low energy consumption and safer from risk of infections. Lastly the slightly uncommon Impeller humidifier uses a rotating disk that pass water through a diffuser and disperse water droplets into the air. It’s safe, portable and does not rely on filter but the drawback is you would need to use clean, purified water to reduce the amount of mineral deposits left in the machine.

    Do I need a Humidifier?

    The keyword is dry. If you stay in a particularly cold area where humidity level is low whole-year long. Another clear sign is you have difficulty sleeping, breathing or feeling discomfort from flaky skin, dry throat and nasal passage. Last but not least, you constantly receive shock from static electricity. then you do need a humidifier.

      Benefits of Humidifier

    • Stop the spread of airborne viruses by reducing the movement of germs due to the combined moisture weight.
    • Humidifier improve sleep and prevent snoring by keeping your airway moisture.
    • Relief itchiness and discomfort from dry cough, sinus by keeping your nasal airway moisture.
    • Prevent flaky, dry skin, bloodshot eyes and chapped lips by retaining the surface moisture.
    • A good level of humidity also makes your home feels warmer (due to less sweat) that in return help converse electricity.
    • Most types of humidifier will run quietly in the background without causing any disruption to your daily activities.
    • Stop almost all static electricity shock that often happen indoor e.g. hanging your laundry clothes.
    • Cheap to own with virtually no recurring cost.
    • Compliment well as 2-in-1 air purifier humidifier combination.

      Disadvantages of Humidifier

    • Most humidifier require frequent maintenance to refill the liquid in the reservoir.
    • Not as effective as air purifier against micron airborne particles. Not great against odor and smoke either.

    How Dehumidifier Works

    Dehumidifier pull moisture from the air to decrease indoor humidity level. Like air purifier, how dehumidifier works its magic is primarily based on the types of machine. The conventional mechanical filter or Refrigerative would draw in air via its fan and pass it over its refrigerated coil. The cold coil would then condense and remove moisture in the air. Absorption or electronic desiccant dehumidifiers is also a popular method that pull air through a rotating water-absorbing material, heated and recirculate dry air back into the room. Suitable for cooler temperature use as the dehumidifier rarely gets frosted. Thermoelectric dehumidifier is the most silent dehumidification method as it uses Peltier pump technology that cools its plate and condenses water vapor. The very slow dehumidification is its biggest setback along with some hassle maintenance due to ice formed in the process. Lastly Ionic membrane dehumidifier remove moisture from the air through electrolysis (separating hydrogen and oxygen). Like Thermoelectric, there are no moving parts or liquid involve during the whole dehumidification process so expect a compact body and a silent operation. Each types of dehumidifier have their own set of pros and cons but in general, here is the benefits of dehumidifier.

    Do I need a Dehumidifier?

    If you experience chest tightness or shortness of breath due to the high humidity condition. There is mold everywhere and on almost every single item in your home. You experience mold-related symptoms like stuffy nose, bloodshot eyes, headache, irregular heartbeat, nausea or chronic fatigue in your home. Lastly, asthmatic/ allergic person, children and elderly that is more prone to respiratory illnesses due to the weaker immune system. Those are the few strong reasons a dehumidifier is indeed needed in your home.

      Benefits of Dehumidifier

    • Ease breathing difficulty and alleviate cough, sinus, headache by absorbing excessive moisture out of the air.
    • Effectively kill off mold and other microbes from growth by cutting off their life source.
    • Dehumidifier also can get rid of musty, rotting smell coming from mold and mildew.
    • A less humid environment also help keep your personal belonging, electronics from mold, rust or corrosion.
    • Dehumidifier help extend your food e.g. bread, cereal freshness without getting stale.
    • Dehumidifier will improve air conditioner energy efficiency and lifespan as the A/C does not need to remove excessive moisture to cool the air.
    • On low speed, dehumidifier will run on background without causing any disturbance.
    • Inexpensive for a portable size dehumidifier that would do a fairly decent job.
    • Like air purifier, dehumidifier also help reduce the amount of dust in your house.

      Disadvantages of Dehumidifier

    • Unable to capture microscopic airborne particles from spreading around the house.
    • Most dehumidifier requires maintenance regularly to clear the collected water out of the reservoir.

    Air Purifier VS Humidifier

    Air Purifier


    Varies that highly dependent on the airflow performance and features of the air purifier.Most mist humidifier is compact as oppose to the heavy-duty, 2-in-1 air purifier humidifier combo.
    Circulates air through its filter to trap airborne allergens like dust mites, mold, pollen, pet dander, germs, bacteria, smoke and odor.Release cool or warm mist to help humidify the air in a room ideally between 30% – 50%.
    Health Benefits
    Stop airborne contaminants from spreading and aggravating health conditions like Sinusitis, Pulmonary Edema, Asthma, or other respiratory issues.Reduce dryness in skin, nose, moisture nasal airways and relieve discomfort from dry cough, dehydration. Also reduce static electricity.
    Does not affect the room humidity level.Increase room humidity level.
    Best Used
    Bedroom, Living hall, Kitchen or places with poor air qualityBedroom, Living hall or places where the air is particularly dry especially during winter.
    • Mechanical (HEPA)  • Activated carbon/ Deodorizer  • UV-light/ Ultraviolet  • PCO cleaner  • Ionic/ Ionizer  • Electrostatic  • Ozone generator• Evaporative  • Steam vaporizer/ Mist  • Ultrasonic  • Impeller
    Target Group
    With the exception of Ozone generator, air purifier is suitable for all age group specially for allergic person and asthma sufferer.For all age group but children must beware of the danger of warm-mist humidifier that can cause burns if gets too close.
    Noise level
    Varies based on airflow output and fan speed the air purifier is in. In general, the more powerful and higher the fan speed is, the louder background noise will be generated.Subtle for ultrasonic, cool mist humidifier while higher but liveable white noise for impeller, warm mist (steam) humidifier.
    Cost with Upkeeping
    For compact air purifier, price start from $20 – $150. Beyond that you will find higher output air purifier with large room size air purifier accountable for the higher price section.Most vaporizer/ cool mist humidifier would only cost between $20 – $50 while larger volume home humidifier or air purifier humidifier combo would cost in the range of $100 – $500.

    The Difference between Air Purifier and Humidifier

    Difference between air purifier and humidifier is not as huge as one would think. Yes air purifier has an overall bigger dimension to fit in its multi-layer filtration, there are still many identical size models notably in either air purifier and humidifier compact/ portable category. You could hardly tell them apart other than one carries a reservoir. Both air purifier and humidifier will alleviate or relieve common irritations like headache, cough, running nose, sore throat and flaky skin through different channel. Air purifier targets airborne particles and allergens via air circulation VS humidifier release moisture into the air that will increase the humidity level of a room. Moving into usability, you can literally use air purifier or humidifier at any corner of the room but we highly recommend placing it in bedroom or living hall where you will likely spend the most time in. Anyone can benefit from air purifier and humidifier but children, asthmatic, allergenic person would probably reap the most. Just make sure children are kept out from fiddling as the air purifier or humidifier may tumble, break or cause mild burn. Noise wise air purifier is distinctly louder even though the comparison is apples to oranges. Finally and perhaps most importantly for some, the cost of ownership. Air purifier in general is much more expensive to own or maintain with its quarter or annual filter replacement than humidifier one-off cost excluding any optional fancy essential oil addon. Maintaining air purifier is much easier as it does not require frequent water refill other than the occasion cleaning. In short, the main differences in air purifier VS humidifier is one purifies your breathing space and one increase the room humidity.


    Air Purifier VS Dehumidifier

    Air Purifier


    Varies from compact to small, medium and large-sized air purifier.Slightly bigger to large body framework capable of fitting in its water tank.
    Circulates air and trap airborne irritants like dust, mold, pollen, pet dander, bacteria, smoke and odor via its filter.Reduce humidity while at the same time stop mold and other microorganisms from growth by drawing moisture in the air.
    Health Benefits
    Stop airborne contaminants from spreading and aggravating health conditions like Sinusitis, Pulmonary Edema, Asthma, or other respiratory issues.Alleviate running nose, cough, headache and prevent respiratory and breathing problems that is likely associated with mold illness.
    Does not affect the room humidity level.Decrease room humidity level.
    Best Used
    Bedroom, Living hall, Kitchen or unventilated places with poor air quality.Basement, Living hall or bedroom where high dampness and musty smell is an issue.
    •  Mechanical (HEPA) •  Activated carbon/ Deodorizer •  UV-light/ Ultraviolet •  PCO cleaner •  Ionic/ Ionizer •  Electrostatic •  Ozone generator•  Mechanical or refrigeration • Absorption/ Electronic desiccant •  Thermoelectric •  Ionic membrane
    Target Group
    Other than ozone generator, air purifier can be used by all age group particularly you are suffering from asthma.Suitable for all with added value for people that is hyper-allergic to mold and other type of fungus.
    Noise level
    Highly dependent on the internal motor and airflow delivery rate, most air purifier generate little noise at low fan speed and loud noise at max speed.Like air purifier, dehumidifier noise level is determined by the moisture output but generally is slight louder than air purifier.
    Cost with Upkeeping
    Small size “compact” air purifier start from $20 – $150. Moving up the chain expect medium-sized air purifier priced between $200 – $400. Anything above that would likely land you a large-sized air purifier. Price start from $30 – $50 for the “mini” version and gradually move up for higher pint capacity, self standing dehumidifier price between $100 – $300.

    The Difference between Air Purifier and Dehumidifier

    Even though this should be a battle between air purifier VS dehumidifier, let’s first get the similarities out of the way. Both air purifier and dehumidifier come in all sizes occupying portable, small, medium to full console category. Anyone from baby, children, adult can truly enjoy the full benefits of dehumidifier and air purifier with the exception of ozone generator (bad for you, bad for all). Same story with background noise, the types, selected speed along with airflow distribution plays a major role in dehumidifier and air purifier output. Price point is also very similar at lower-end category but the gap widens for higher-end models with air purifier calling higher shot because of the complexity filtration and added features. Finally, both air purifier and dehumidifier can mitigate pain and discomfort like cough, sneeze, headache or breathing problems that is often corelated by mold. As for the difference between air purifier and dehumidifier, air purifier works by circulating air that go through its internal filter to trap airborne irritants like dust, mold, pollen, smoke to the extent of germs, bacteria and viruses. On the other hand, dehumidifier works by sucking out moisture from the air to stop ground mold and other microbes that thrive on moisture from growth. A perfection combination with air purifier able to quickly resolve on-going issue and dehumidifier giving it a permanent fix. You can run air purifier and humidifier in same room and at all places but bedroom is very likely the place to be as we spent the most time in or for dehumidifier case, basement due to the poor ventilation that often lead to high dampness level. Maintenance wise, the difference between air purifier and dehumidifier is the later has a higher frequency rate because you have clear out the water in the water tank when it gets full before resuming operation. In summary, air purifier and dehumidifier will help improve our room air quality with each using a different methodology.


    Humidifier VS Dehumidifier



    Typically compact in size unless is the full-sized version or air purifier humidifier combination.Beside the renewable or portable version, most dehumidifer has medium to large body with a removable water tank.
    Raise room humidify to an ideal 30% – 50% via the emission of cool or warm mist.Reduce room humidity that is over 50% by absorbing moisture in the air. Mold and other microbes would fail to thrive without sufficient moisture.
    Health Benefits
    Moisture skin, nasal passage airways while alleviate dry cough and throat irritation. Humidifier also indirectly help reduce static electricity.Prevent mold-related allergies and symptoms like sinus, running nose, cough, headache that in long-run would lead to serious respiratory issues.
    Increase humidity level.Decrease humidity level.
    Best Used
    Places you spend the most time in like bedroom, living hall particularly during winter time where humidity is low.Basement, living hall or bedroom covered with musty smell particularly during summer time where humidity is low.
    • Evaporative  • Steam vaporizer/ Mist  • Ultrasonic  • Impeller•  Mechanical or refrigeration • Absorption/ Electronic desiccant •  Thermoelectric •  Ionic membrane
    Target Group
    Suitable for all but folks with children need to be extra cautious on heat produced in warm-mist humidifier.Suitable for all from children, adult to elderly that would be at risk of mold infection.
    Noise level
    Subtle to soft for ultrasonic, cool mist humidifier while liveable white noise for impeller, warm mist (steam) humidifier.Louder but manageable noise level that can be curbed depending on the speed or placement.
    Cost with Upkeeping
    Cheap for a compact vaporizer/ cool mist humidifier between $20 – $50. Expect price starting from $100 all the way to $500 for bigger models or air purifier humidifier combo.Mini/ portable dehumidifier is starting at an affordable price from $30 – $50. Expect an estimated price between $100 – $300 for a full-sized 30 – 70 pint dehumidifier.

    The Difference between Humidifier and Dehumidifier

    In ideal situation, humidity in a room would fall between the recommended 30% to 50%. In real-life, humidity is a climate variable that is affected by weather (heatwave/ rainfall), season (summer/ winter), location (basement/ air condition) and human factors (poor ventilation/ deforestation). Change is possible with many ways to go about it but let us focus on the use of home appliances i.e. humidifier and dehumidifier. While both machines are designed to help control the humidity level in a room, the big difference between humidifier and dehumidifier is the former add moisture into the air and the later reduce moisture from the air. In other words, humidifier would bring the humidity up through the release of cool or warm mist while dehumidifier would bring the humidity down by absorbing moisture from the air. Both humidifier and dehumidifier can create a more comfortable environment for person that is suffering from dryness, cough, sinus or nasal congestion; dehumidifier is better known for its contribution in stopping Toxic Black Mold and other microorganism from growth. With the right level of humidity, everyone from children, elderly to asthmatic patient would enjoy the full benefits of humidifier and dehumidifier. You can literally use both machines anywhere with humidifier popular for bedroom as it can keep skin hydrated while dehumidifier is often use in basement where high dampness along with musty smell roam. Noise level favors more to humidifier VS dehumidifier traditional refrigeration or desiccant mechanism. Lastly, the difference between humidifier and dehumidifier is the price point with humidifier is slightly cheaper but costlier to maintain. So to recap, humidifier would be used if the humidity level falls below 30 – 35% VS dehumidifier that is used if the humidity level is greater than 50%.


    Air Purifier VS Humidifier VS Dehumidifier

    Air Purifier



    Small to Large Typically smallSmall to Large
    Purify Air
    Humidity Level
    Not affected Increase Decrease
    Variants (Types)
    Quarterly to AnnuallyRegularlyRegularly
    Noise Level
    Soft to Loud Soft to AverageAverage to Loud
    Cost including Upkeeping
    Highest CheapestAverage

    Leaf humidifier
    Try not to get this humidifier that requires you to fill in unknown substances

    When should you use a humidifier or dehumidifier?

    If you have symptoms such as dry throat, flaky skin, sneezing and coughing especially just after waking up, chances are the humidity level in your room is way too low. Get a humidifier to increase the humidity level in your room. If you room its constantly infested with mold/ pollen/ dust mites, get a dehumidifier to reduce the humidity level and thus prevent mold from growing. Typically, children and people suffering from allergies such as asthma are more prone to this issue. High humidity level is the perfect environment for mold, pollen and dust mite to grow and flourish.

    There are also the seasonal allergies that parents should be well-aware. In my country, we have a seasonal haze that will invade us in a yearly basis. During that period, majority of the air purifier/ humidifier would be sold off and there is limited room for price bargaining. So please be well prepare up front.

    How About Air Purifier With built-in Humidifier? Yay or Nay?

    I will strongly recommend getting an Air purifier with built-in humidifier unless you have a budget constraint. There is no difference between the two in terms of humidifying features. However, with an air purifier humidifier, it has the additional features of removing unwanted particles such as mold, pollen, dust, pet dander and even bad odor; humidifier can boost the effectiveness of the air purifier. Both would perfectly complement each other. By using air purifier with humidifier, it can run both simultaneously that not only will save you a bundle on purchasing one less unit, you will also save on your electricity bill due to the low energy consumption thus contribute to a greener mother nature. Best of all, since both air purifier and humidifier requires regular cleaning & maintenance, you would only have to keep track and maintain 1 unit. One downside though an air purifier humidifier will cost more than a stand-alone humidifier.

    In summary,

    • Humidifier and dehumidifier serve the opposite functions. Humidifier increase moisture into the air and dehumidifier decrease moisture from the air.
    • If the room humidity level is below 30%, get a humidifier, above 50%, get a dehumidifier. The recommended level for humidity is between 30% to 50%
    • Generally, summer air = high humidity, winter air = low humidity
    • Most air purifier, humidifier/ dehumidifier comes with a humidity monitor built-in so an external humidity monitor is not necessarily
    • If you have “sick” symptoms e.g. dry skin, sinus, dry throat or asthma, get a humidifier
    • If you room is constantly infested with mold, pollen, dust mites, get a dehumidifier
    • If budget is not a main concern, consider an air purifier humidifier over a stand-alone humidifier.

    And above all else, please note that both humidifier and dehumidifier can only play the part as the contributor. You will still need an air purifier to effectively clean your air. I hope by now you will have a good understanding on this, if not feel free to drop me a question on the comment section below.

    10 thoughts on “Air Purifier VS Humidifier VS Dehumidifier : Combo and Differences”

    1. Hi. What is the best air purifier with humidifier.. That’s is most compact and good looking.. Doesn’t matter about price.. Just want one that’s good, pretty, compact, and easy to maintain.

    2. Thanks for the above.

      But I am confused you wrote “If you have “sick” symptoms e.g. dry skin, sinus, dry throat or asthma, get a humidifier”

      But then again above that you wrote ” If you room its constantly infested with mold/ pollen/ dust mites, get a dehumidifier to reduce the humidity level and thus prevent mold from growing. Typically, children and people suffering from allergies such as asthma are more prone to this issue.”

      Which seen to be saying if those with asthma are affected by mold/ pollen/ dust mites, get a humidifier or a dehumidifier?

      1. Hi Ken,

        Just follow the simple rules, if the humidity level is below 30%, get a humidifier. Anything above 50%, get a dehumidifier. You will need an humidifier reader to check on the level.

    3. Hi Sir i would like to ask if this Hitachi EP -A3000 can help co’z i always sneeze every morning and my eyes is teary almost everyday,, im working in a ship and leaving in a cabin

      Thank you

    4. How about combination Air Conditioner with Air Purifier + Humidifier, is there a product for that combo?
      I live in tropic country and I have asthma. What do you suggest for me to used?

      1. Not that I’m aware of. Not sure if you need a humidifier in tropic country but I would recommend a stand-alone air purifier as you could leave the unit turn on for 24/7.

    Leave a Reply

    Your email address will not be published. Required fields are marked *